【摘要】 为实现室内育种多通道温湿度的信号采集,采用基于过采样原理的∑-△模数转换器(ADC)及FPGA的方案更为方便简单。针对温湿度采集的低成本、低精度要求,选择了由FPGA的低压差分输入端(LVDS)及其内部的抽取型级联积分梳状(CIC)滤波器实现的一阶ADC。该ADC分辨率达到12位,转换时间约为350μs,温湿度测量精度完全满足同类型系统指标要求,可作慢信号采集的通用ADC。通过ChipScope在线调试和改进调理电路,使得测量误差进一步减小。还可采用高阶ADC满足高精度多种类模拟信号测量,具有适用性强、成本低、功耗低,且集成度高等特点。更多还原

【Abstract】 It is more convenient for FPGA-based systems to use ∑-△ ADC based on oversampling principle, for the realization of a multi-channel temperature and humidity signal acquisition system in an incubation room. To meet the low cost and low precision requirements of temperature and humidity acquision, the system chooses a first-order ADC, consisting of a low-voltage differential signaling( LVDS) and a cascaded integrator-comb( CIC)filter. The ADC resolution is 12-bit and its conversion time is about 350 μs, so it can be used as a slow signal acquisition universal ADC with accuracy meeting the same type of system indicators. Through ChipScope online debugging and improving the conditioning circuit, the measurement error is further reduced. A high-order ADC can be used to meet the requirement of high-precision multi-class data measurement. The system has the characteristics of strong applicability, low cost, low power consumption and high integration.更多还原